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/* timer test programm for timer1: 16bit with normal mode */
#include <avr/interrupt.h>
volatile int timer_ticks;
#ifdef T3TEST
ISR(TIMER3_OVF_vect) {
timer_ticks++;
}
ISR(TIMER3_COMPB_vect) {
timer_ticks++;
}
#else
ISR(TIMER1_OVF_vect) {
timer_ticks++;
}
#endif
int main(void) {
volatile int tmp;
#ifdef T3TEST
TCNT3H = 0; /* Timer 3 by CLK/1 */
TCNT3L = 0;
OCR3AH = 0x06;
OCR3AL = 0x3f; /* factor = 1600, PWM frequency = 5kHz */
OCR3BH = 0x02;
OCR3BL = 0x7f; /* duty factor 40% = 640 */
DDRE = 0x10; /* PE4 = out */
TCCR3A = 0x30 + 0x03; /* comB = 3, wgm = 15 */
TCCR3B = 0x18 + 0x01; /* wgm = 15, cs=1 */
ETIMSK = _BV(TOIE3) + _BV(OCIE3B);
#else
TCNT1H = 0; /* Timer 1 by CLK/1 */
TCNT1L = 0;
TCCR1B = 0x01; /* 16,384ms on 4MHz, normal mode */
#ifdef PROC_atmega48
TIMSK1 = _BV(TOIE1);
#else
TIMSK = _BV(TOIE1);
#endif
#endif
sei();
tmp = timer_ticks;
while(1) {
if(tmp != timer_ticks) {
tmp = timer_ticks;
}
}
return 0;
}
/* EOF */
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